I recently installed vista on my imac via bootcamp, and wanted a little more space so I opted for 32g+/ntfs formatting. As I understand, though, this means less compatibility in regards to reading and writing files between the two. I am curious if -- were I to buy an external hard drive -- I would be able to easily share files (itunes library, some graphics work, etc) between the two OSes, and ideally, also use the said HD for time machine back up. If so, does anyone have any recommendations on external HDDs? it really need not be more than 160gb. Thanks for any help.